In what CBCP News said was a setback for Reproductive Health bill lobbyists, WHO International Agency for Research on Cancer (IARC) tagged the oral combined estrogen-progestogen contraceptives as “carcinogenic to humans.”

The report classified the hormone pill under Group 1 carcinogens, alongside asbestos, arsenic, formaldehyde, and plutonium.

“There is sufficient evidence in humans for the carcinogenicity of oral combined estrogen–progestogen contraceptives. Oral combined estrogen–progestogen contraceptives cause cancer of the breast, in-situ and invasive cancer of the uterine cervix, and cancer of the liver,” the report read.

This is the third time that IARC assessed the carcinogenicity of the pills. Similar studies were done in 1988 and 2005.

The 2011 report also said: “A large body of evidence was evaluated for several organ sites, among which the Working Group concluded there are increased risks for cancer of the breast in young women among current and recent users only…”

There was also increased risk for “in-situ and invasive cancer of the uterine cervix, and for cancer of the liver in populations that are at low risk for HBV [Hepatitis B virus] infection (this risk is presumably masked by the large risk associated with HBV infection in HBV-endemic populations),” the report said.

“In addition, for cancer of the uterine cervix, the magnitude of the associations is similar for in-situ and invasive disease, and the risks increase with duration of use, and decline after cessation of use,” it added.

Pro-life groups have several times called on RH bill supporters to bare information on the side effects of the hormone pills.

They noted the bill, for one, is being pushed under the pretext of “informed choice.”